A cap for closing a container, a combination of a cap and a neck

ABSTRACT

A combination comprises a cap for a container and a neck of a container. The neck is delimited by an outer surface from which a circular enlargement projects, the outer surface extending up to a rim of the neck. The cap comprises a side wall extending about an axis. A separation line is provided on the side wall for defining a retaining ring intended to engage with the circular enlargement to remain anchored to the neck of the container and a closure element removably engageable with the neck so as to be movable between a closed position and an open position. The separation line extends about the axis and is circumferentially interrupted so as to leave a joining portion between the retaining ring and the closure element. The cap further has an incision line which extends transversally to the axis between the separation line and a free edge of the retaining ring, so that two connecting bands are defined between the separation line and the incision line, the connecting bands joining the retaining ring to the joining portion. The connecting bands are deformable for allowing the joining portion to rotate when the closure element is moved from the closed position to the open position, so that an edge of the joining portion which, in the closed position, faces the retaining ring, is facing towards the rim of the neck in the open position.

This invention relates to a cap for a container, in particular a caphaving a retaining ring, which can be associated with a neck of thecontainer, the cap further having a closure element which, afteropening, remains connected to the retaining ring. The cap according tothe invention is particularly, but not exclusively, suitable for beingapplied to bottles intended to contain liquid substances.

The invention further relates to a combination of a cap and of a neck ofa container.

In addition, the invention relates to a method for the production of acap for a container.

Caps for bottles are known, which comprise a cup-shaped body providedwith an inner thread suitable for engaging with an outer thread of aneck of the bottle. The known caps are further provided with atamper-evident ring connected to the cup-shaped body by a plurality ofbreakable elements. When the cap is opened for the first time, thecup-shaped body separates from the tamper-evident ring due to breakageof the breakable elements. The tamper-evident ring remains associatedwith the neck of the bottle, whilst the cup-shaped body can be unscrewedby the user, which in this way separates the cup-shaped body from thebottle to access the contents of the bottle. Subsequently, thecup-shaped body can be screwed again on the neck to reclose the bottle.

Sometimes, after the bottle has been emptied, the user throws thecup-shaped body on the ground, either intentionally or accidentally,whilst the bottle, together with tamper-evident ring associated thereto,is correctly disposed of in a waste bin.

To overcome this drawback, caps have been proposed which are providedwith a retaining ring, which can be associated with a neck of a bottle,and a closure element, connected to the retaining ring by a hinge. Theclosure element can be rotated about the hinge between an open position,in which a user can access the contents of the bottle, and a closedposition, in which the closure element prevents access to the bottle.The hinge keeps the closure element associated with the retaining ringand, therefore, with the bottle, thereby preventing the closure elementfrom being thrown on the ground independently of the bottle.

The known caps provided with a hinge have however the drawback of beingrather complicated to be manufactured. In effect, the hinge is usuallyproduced in the same mould in which the cap is obtained, particularly byinjection moulding or compression moulding.

In order to produce the caps with a hinge of known type it is thereforenecessary to provide special moulds, different from those which arenormally adopted for producing the caps free of the hinge. These mouldsare more complicated than the ordinary ones, in particular because thecaps with hinge of known type may have undercut parts, which thusrequire special means in order to be extracted from the mould.

Moreover, the caps with a hinge of known type may have zones with a veryreduced thickness, which are difficult to obtain because the moltenpolymeric material flows with difficulty in the portions of the mouldintended to form these zones.

This increases the costs for the production of the caps with hingeand/or the cycle time necessary to obtain them.

In caps with a hinge of the known type, sometimes the closure element,after having been moved to the open position, prematurely recloses byrotating about the hinge. It may also happen that the closure elementpartly rotates about the hinge, thereby moving into a vertical, oralmost vertical configuration. In these cases, the closure element mayin an unwelcome way strike the face of a user, who is drinking from thebottle to which the cap with hinge is applied, or be interposed in thedesired way between the bottle and a container, for example a glass,into which a liquid contained in the bottle is poured.

Moreover, in caps with a hinge of the known type, when the closureelement has been moved to the open position, the retaining ring, whichremained associated with the neck, is free to rotate about the neckitself. Therefore, it may happen that, whilst a user is drinking aliquid contained in the bottle to which the cap with a hinge is applied,or is pouring the liquid contained in the bottle into a glass, theretaining ring rotates about the neck due to the force of gravity,together with the closure element. If that occurs, the closure elementmay strike the face of the user who is drinking, or be interposedbetween the neck of the bottle and the glass, which obstructs thedispensing of the liquid into the glass.

An object of the invention is to improve the caps of known type,particularly the caps comprising a retaining ring intended to remainassociated with a neck of the container and a closure element which mayremovably engage with the neck to allow a user to open or alternativelyclose the container.

Another object is to provide a cap for a container, of the typementioned above, which can be produced simply.

A further object is to provide a cap for a container, provided with aclosure element that remains connected to the retaining ring which doesnot require very complicated moulds for its production.

A further object is to provide a cap for a container, comprising aclosure element that remains connected to the retaining ring, whereinthe closure element is kept stably in an open position.

Another object is to provide a cap for a container wherein, in the openposition, there is reduced risk of the closure element accidentallystriking the face of the user or obstructing the dispensing of asubstance contained in the container into a glass or the like.

In a first aspect of the invention, there is provided a combination of acap for a container and of a neck of a container,

wherein the neck is delimited by an outer surface from which a circularenlargement projects, the outer surface extending up to a rim of theneck,

and wherein the cap comprises a side wall extending about an axis, aseparation line being provided on the side wall for defining:

-   -   a retaining ring intended to engage with the circular        enlargement to remain anchored to the neck,    -   and a closure element which can removably engage the neck so as        to be movable between a closed position and an open position,

wherein the separation line extends about the axis and iscircumferentially interrupted so as to leave a joining portion betweenthe retaining ring and the closure element,

wherein the cap further has an incision line which extends transversallyto the axis between the separation line and a free edge of the retainingring, so that two connecting bands are defined between the separationline and the incision line, the two connecting bands joining theretaining ring to the joining portion,

and wherein the connecting bands are deformable to allow the joiningportion to rotate when the closure element is moved from the closedposition to the open position, so that an edge of the joining portionwhich, in the closed position, faces the retaining ring, is facingtowards the rim of the neck in the open position.

Owing to this aspect of the invention, it is possible to obtain a capcapable of stably remaining in the open position. In effect, when thejoining portion rotates whilst the closure element passes from theclosed position to the open position, interference occurs between thejoining portion and the neck of the container. This interferencepersists even in the open position. In order to bring the closureelement back to the closed position, a predetermined force has to beapplied to the closure element, so as to overcome the interferencebetween the neck and the joining portion. This makes it difficult, ifnot impossible, for the closure element to return to the closed positionon its own.

In more detail, in the open position, the joining portion rests on theneck of container and the connecting bands, which have been deformed,apply on the joining portion a force which tends to keep the joiningportion in contact with the neck of the container. That causes theinterference between the joining portion and the neck of the container,which stably keeps the closure element in the open position.

Owing to the interference between the joining portion and the neck,rotation of the cap, in particular of the retaining ring, about theneck, is also obstructed.

In an embodiment, the connecting bands are deformable by a twistingmovement when the closure element is moved from the closed position tothe open position.

This twisting movement may affect at least one part of the height ofeach connecting band, the height being defined as the dimension of theconnecting band in a direction parallel to the axis, in the closedposition of the closure element.

This makes is possible to rotate the joining portion as previouslydescribed, without providing fracture or weakening lines placed betweenthe joining portion and the connecting bands. Consequently production ofthe cap is facilitated.

Whilst the joining portion rotates and its edge slides in contact withthe neck until it reaches the open position in which the edge of thejoining portion is facing towards the rim of the neck, an interferenceis generated between the joining portion and the neck, which reaches amaximum value when the joining portion is substantially perpendicular tothe neck, and which is reduced (but without reaching a null value) afterthe joining portion has overturned and is resting on the neck with theedge facing upwards.

The user who moves the closure element towards the open position noticesthat the position in which the interference is at its maximum has beenpassed, since his/her hand perceives a sort of vibration which makeshe/she understand that the closure element has been stably moved to theopen position. That is welcomed by the user, who has the certainty ofhaving correctly opened the container.

In an embodiment, the distance between the separation line and theincision line is equal to, or greater than, 1.5 times half thedifference between the external diameter of the circular enlargement andthe diameter of the outer surface of the neck, immediately above thecircular enlargement.

The above-mentioned distance is measured parallel to the axis of theside wall, when the closure element is in the closed position. Thisdistance therefore corresponds to the height of the connecting bands.

Experimentation has shown that the values of the distance between theseparation line and the incision line mentioned above guarantee that theconnecting bands deform correctly when the closure element passes fromthe closed position to the open position. In particular, if the distancebetween the separation line and the incision line satisfies thecondition indicated above, a condition of interference between thejoining portion and the neck occurs which is very favourable for keepingthe closure element in the open position.

It is preferable for said distance between the separation line and theincision line to be equal to, or greater than, 2 times half thedifference between the external diameter of the circular enlargement andthe diameter of the outer surface of the neck, immediately above thecircular enlargement.

It is even more preferable for said distance between the separation lineand the incision line to be equal to, or greater than, 2.5 times halfthe difference between the external diameter of the circular enlargementand the diameter of the outer surface of the neck, immediately above thecircular enlargement.

In an embodiment, the joining portion has an angular dimension about theaxis of the side wall, greater than, or equal to, 20°, preferablygreater than, or equal to, 25°.

In an embodiment, the joining portion has an angular dimension about theaxis of the side wall which is less than, or equal to, 120°, preferablyless than, or equal to, 90°.

In this way, the joining portion is not too wide about the axis of theside wall, which would make it difficult for the joining portion tooverturn, that is to say for its edge to pass from a configurationfacing the retaining ring, to a configuration facing towards the rim ofthe neck.

At the same time, the joining portion is not too narrow about the axisof the side wall, which could generate an interference, between thejoining portion and the neck, which is not sufficient to keep theclosure element stably in the open position.

In an embodiment, the neck is provided with at least one fixing elementsuitable for engaging with the closure element to allow the closureelement to be removably fixed to the neck.

The at least one fixing element may comprise a thread having one or morestarts.

Preferably but not necessarily, the distance between the circularenlargement and the at least one fixing element is greater than, orequal to, half of the distance between the separation line and theincision line.

In this way, between the circular enlargement and the at least onefixing element there is a space sufficient for receiving the joiningportion, without the edge of the latter interfering with the at leastone fixing element.

In an embodiment, the circular enlargement is delimited, towards the rimof the neck, by a truncated cone shaped surface.

In an embodiment, a generatrix of the truncated cone shaped surfaceforms an angle less than, or equal to, 35° with a straight line parallelto a longitudinal axis of the neck.

Preferably, the above-mentioned angle is 30°.

In this way, the closure element can easily be positioned in an openposition in which it forms a sufficiently large angle of opening withthe neck.

In an embodiment, the separation line extends in a portion of the sidewall in which a plurality of knurling lines is provided.

That is to say, the separation line intersects the knurling linesprovided on the side wall of the cap.

That allows maximisation of the height of the connecting bands, withoutcompromising the capacity to grip the cap by a user or a cappingmachine. Alternatively, the separation line may extend in a portion ofthe side wall externally delimited by a smooth surface, that is to say,a surface free of knurling lines.

In a second aspect of the invention, there is provided a cap for acontainer, comprising a side wall extending about an axis and atransversal wall arranged at an end of the side wall, a separation linebeing provided on the side wall for defining:

-   -   a retaining ring intended to remain anchored to a neck of the        container, and    -   a closure element which can removably engage the neck, so as to        open or close the container;

wherein the separation line extends about the axis and iscircumferentially interrupted so as to leave a joining portion betweenthe retaining ring and the closure element, the joining portion defininga hinge band which extends between two opposite end zones of the joiningportion,

the cap further having an incision line which extends transversally tothe axis between the separation line and a free edge of the retainingring, so that two connecting bands are defined between the separationline and the incision line, the two connecting bands joining theretaining ring to the opposite end zones of the joining portion.

The joining portion makes it possible to keep the closure element stablyassociated with the retaining ring and therefore with the neck of thecontainer. This prevents the closure element from being thrown on theground separately from the container. This thus increases theprobability that the closure element, together with the container, iscorrectly disposed of together with waste of the same type, inparticular together with plastic material waste.

The cap provided by the second aspect of the invention may be producedin a relatively simple manner, without the need to use special moulds.In effect, the cap provided by the second aspect of the invention can beproduced in a traditional mould, if the incision line is made by acutting operation. It is possible by the cutting operation to obtain anincision line passing through the entire thickness of the side wall, oran incision line which does not pass through, at which the thickness ofthe side wall is cut only partially.

It is also possible to produce the incision line by moulding, inside themould in which the cap is produced, but without, however, causingexcessive complications of the mould, owing to the particularly simpleshape of the incision line. In this case, the incision line may even beshaped as a weakening line.

Since the incision line lies between the separation line and the freeedge of the retaining ring, the incision line does not weaken thejoining portion. In the cap provided in the second aspect of theinvention, the joining portion is therefore relatively sturdy, whichmakes it more difficult to accidentally separate the retaining ring fromthe closure element.

The connecting bands, together with the joining portion, define a hingearrangement which has a capacity for movement, in an axial direction,noticeably greater than the capacity for movement which would be allowedby the joining portion alone.

In effect, that hinge arrangement makes it possible to move the closureelement away from the retaining ring along a significant axial distance,determined by the combination of the length of the connecting bands andof the joining portion. In this way the closure element can be easilydisengaged from the neck of the container.

In an embodiment, the joining portion has an angular dimension about theaxis of the side wall, greater than, or equal to, 20°, preferablygreater than, or equal to, 25°.

In an embodiment, the joining portion has an angular dimension about theaxis of the side wall which is less than, or equal to, 120°, preferablyless than, or equal to, 90°.

That allows the joining portion to rotate when the closure element ismoved from a closed position to an open position, so that an edge of thejoining portion which, in the closed position, faces the retaining ring,is facing towards a rim of the neck in the open position. In this way itis possible to obtain the advantages previously described with referenceto the first aspect of the invention, in particular relative to theclosure element which is stably kept in the open position.

In an embodiment, the connecting bands may be arranged symmetrically toeach other relative to a plane containing the axis of the side wall anda centre line of the joining portion.

This symmetrical shape allows a reduction in the involuntary movementsof the closure element when the cap is in an open position, inparticular limiting its lateral movements.

In an embodiment, the joining portion has a thickness substantiallyconstant on a plane containing the separation line.

That makes the cap of the second aspect of the invention even simpler tomake, since special moulds are not necessary for producing triangularhinges or very thin joining lines.

In a third aspect of the invention, a method is provided comprising thesteps of:

-   -   producing a cap for a container, the cap comprising a side wall        extending about an axis and a transversal wall arranged at an        end of the side wall,    -   providing a separation line on the side wall for defining a        retaining ring intended to remain anchored to a neck of the        container, and a closure element which can removably engage the        neck, so as to open or close the container, wherein the        separation line extends about the axis and is circumferentially        interrupted so as to leave a joining portion between the        retaining ring and the closure element,    -   making an incision line which extends transversally to the axis,        so that two connecting bands are defined between the separation        line and the incision line, the two connecting bands joining the        retaining ring to the joining portion.

The method according to the third aspect of the invention makes itpossible to obtain, in a particularly simple manner, a cap wherein theclosure element remains associated with the retaining ring.

In a fourth aspect of the invention, there is provided a cap for acontainer, comprising a side wall extending about an axis and atransversal wall arranged at an end of the side wall, a separation linebeing provided on the side wall for defining:

-   -   a retaining ring intended to remain anchored to a neck of the        container, and    -   a closure element which can removably engage the neck, so as to        open or close the container;

wherein the separation line extends about the axis and iscircumferentially interrupted for defining a joining portion having anangular dimension about the axis,

the cap further having a first incision line and a second incision line,which extend transversely to the axis for delimiting the joining portionon opposite sides, the first incision line and the second incision linehaving respective angular extensions about the axis greater than theangular dimension of the joining portion.

The joining portion makes it possible to keep the closure element stablyassociated with the retaining ring and therefore with the neck of thecontainer. This prevents the closure element from being thrown on theground separately from the container. This thus increases theprobability that the closure element, together with the container, iscorrectly disposed of together with waste of the same type, inparticular together with plastic material waste.

The cap according to the fourth aspect of the invention may be producedin a relatively simple manner, without need to use special moulds. Ineffect, the cap according to the fourth aspect of the invention can beproduced in a traditional mould, if the first incision line and thesecond incision line are made by a cutting operation. It is possible bythe cutting operation to obtain incision lines passing through theentire thickness of the side wall, or incision lines which do not passthrough, at which the thickness of the side wall is cut only partially.

It is also possible to consider the production of the first incisionline and the second incision line by moulding, inside the mould in whichthe cap is produced, but without, however, causing excessivecomplications of the mould, owing to the particularly simple shape ofthe first incision line and the second incision line. In this case, thefirst incision line and the second incision line may be shaped asweakening lines.

Since the first incision line and the second incision line lie onopposite sides of the joining portion, the first incision line and thesecond incision line do not weaken the joining portion. In the capaccording to the fourth aspect of the invention, the joining portion istherefore relatively sturdy, which makes it more difficult toaccidentally separate the retaining ring from the closure element.

In an embodiment, the first incision line delimits at least partially aconnecting band and a further connecting band which connect theretaining ring to the joining portion.

The connecting band may be defined between a peripheral part of thefirst incision line and an end portion of the separation line.

The further connecting band may be defined between a further peripheralpart of the first incision line and a further end portion of theseparation line.

The joining portion is interposed between the end portion and thefurther end portion of the separation line.

In an embodiment, the second incision line delimits at least partially aconnecting strip and a further connecting strip which connect theclosure element to the joining portion.

The connecting strip may be defined between a peripheral portion of thesecond incision line and an end portion of the separation line.

The further connecting strip can be defined between a further peripheralportion of the second incision line and a further end portion of theseparation line.

The retaining ring is thus connected to the joining portion by theconnecting band and the further connecting band, which converge in thejoining portion from two regions of the retaining ring spaced apart fromeach other.

The closure element is in turn connected to the joining portion by theconnecting strip and the further connecting strip, which converge in thejoining portion from two regions of the closure element spaced apartfrom each other.

The connecting band, the further connecting band, the connecting stripand the further connecting strip define a hinge arrangement which isparticularly robust and effective.

In effect, the hinge arrangement makes it possible to move the closureelement away from the retaining ring along a significant axial distance,determined by the combination of the length of the connecting band andthe connecting strip (or by the combination of the length of the furtherconnecting band and the further connecting strip). In this way theclosure element can be easily disengaged from the neck of the container.

The joining portion guarantees that the hinge arrangement has a goodresistance, which for the same length is certainly greater than a hingedefined by only two bands parallel to each other, which are notconnected to each other.

This reduces the risk that the closure element can be accidentallydetached from the retaining ring, as well reducing the possibility oflateral misalignments of the closure element when the cap is moved to anopen position.

In an embodiment, the connecting band and the connecting strip may bearranged symmetrically to the further connecting band and, respectively,to the further connecting strip relative to a plane containing the axisof the side wall and a centre line of the joining portion.

This symmetrical shape reduces the involuntary movements of the closureelement when the cap is in an open position, in particular limiting thelateral movements of the closure element.

In an embodiment, in an open position, the closure element is rotatableabout an ideal line passing through an end of the second incision lineand through a further end of the second incision line, so that an edgezone of the closure element diametrically opposite the joining portioncan be moved close to the joining portion for engaging with the neck.

This makes it possible to keep the closure element stably spaced fromthe neck in the open position, thereby preventing the closure elementfrom tending to reclose accidentally.

The invention can be better understood and implemented with reference tothe accompanying drawings which illustrate some non-limiting exampleembodiments of it and in which:

FIG. 1 is a perspective view of a cap for a container, in a closedposition;

FIG. 2 is a side view of the cap of FIG. 1, in a configuration wherein aclosure element of the cap is separated from a retaining ring;

FIG. 3 is a perspective and interrupted view of the cap of FIG. 1,applied on a neck of a container, in a configuration wherein a closureelement of the cap is moved to a lateral position relative to the neck;

FIG. 4 is a perspective view of a cap according to an alternativeembodiment, in a configuration wherein a closure element of the capbegins to be separated from the retaining ring;

FIG. 4a shows an enlarged detail of FIG. 4;

FIG. 5 is a side view showing a cap for a container, according to analternative embodiment;

FIG. 6 is a view like that of FIG. 5, from the direction D indicated inFIG. 5;

FIG. 7 is a side view like that of FIG. 5, in a configuration wherein aclosure element of the cap is separated from a retaining ring;

FIG. 8 is a side view of a neck on which the cap of FIG. 5 may bescrewed;

FIG. 9 is a perspective view of the neck of FIG. 8;

FIG. 10 is side view, showing the cap of FIG. 5, applied on the neck ofFIG. 8, the closure element of the cap being arranged in an openposition;

FIG. 11 is a perspective view of a cap for a container, in a closedposition;

FIG. 12 is a side view of the cap of FIG. 11, in the closed position;

FIG. 13 is a side view of the cap of FIG. 11, in a configuration inwhich a closure element of the cap is separated from a retaining ring;

FIG. 14 is a perspective view of the cap of FIG. 11, applied to a neckof a container, in an open position;

FIG. 15 is a view like that of FIG. 14, wherein the closure element ofthe cap interferes with the neck to remain stably open.

FIG. 1 shows a cap 1 for closing a container, particularly a bottleintended to contain a liquid substance such as a drink. The cap 1 ismade of polymeric material. Any polymeric material suitable for mouldingmay be used to obtain the cap 1.

The cap 1 is shown in FIG. 1 in a closed position in which the cap 1 iswhen it leaves a cap production line, ready to be applied on thecontainer. In this condition, the cap 1 comprises a side wall 2 whichextends about an axis Z, and a transversal wall 3 arranged at an end ofthe side wall 2, so as to close that end. The transversal wall 3 extendstransversally, in particular perpendicularly, to the axis Z. Thetransversal wall 3 may be flat, even though other shapes aretheoretically possible. In the example illustrated, the transversal wall3 has a substantially circular shape in plan view.

The cap 1 has a separation line 4, positioned on the side wall 2 andextending about the axis Z. The separation line 4 extends on a planearranged transversally, in particular perpendicularly, to the axis Z.The separation line 4 defines on the cap 1 a retaining ring 5 and aclosure element 6. The latter are positioned on opposite sides of theseparation line 4. As described in more detail below, when the cap 1 isbrought to an open position, the closure element 6 separates from theretaining ring 5 along the separation line 4.

Along the separation line 4 a plurality of breakable bridges 7 may beprovided, which connect the retaining ring 5 to the closure element 6.The breakable bridges 7 are intended to be broken the first time the cap1 is moved to the open position, to signal that the container is nolonger intact. The separation line 4 may be parallel to a free edge 16of the cap 1. More specifically, the free edge 16 delimits the retainingring 5 on the opposite side to the transversal wall 3.

The separation line 4 does not extend for an entire angle of 360° aboutthe axis Z. The separation line 4 is interrupted in the circumferentialdirection, so as to define on the side wall 2 a joining portion 8, atwhich the closure element 6 remains joined to the retaining ring 5.

In other words, the separation line 4 has a first end 9 and a second end10. The joining portion 8 is interposed between the first end 9 and thesecond end 10. At the joining portion 8, the retaining ring 5 is joinedto the closure element 6.

As shown in FIG. 1, the joining portion 8 has an angular dimension Wabout the axis Z.

The joining portion 8 defines a hinge band about which the closureelement 6 can rotate after disengaging from a neck 18, shown in FIG. 3,of the container on which the cap 1 is applied.

This hinge band extends between two opposite end zones of the joiningportion 8, that is to say, it extends from a zone of the joining portion8 immediately adjacent to the first end 9 to a zone of the joiningportion 8 immediately adjacent to the second end 10.

The hinge band defined by the joining portion 8 therefore affects theentire angular dimension W of the joining portion 8, withoutinterposition of arrow shaped hinges or of reduced thickness zones.

In the example illustrated, the closure element 6 has a cup-shaped bodyand comprises a skirt 11 which extends about the axis Z. The skirt 11 isconnected to the transversal wall 3, arranged at the end of the skirt 11opposite the separation line 4. In particular, the skirt 11 is connectedto the transversal wall 3 by a connecting zone 12, which may be shaped,in cross section, like a beveled edge or a circular connection zone.

The skirt 11 has, on an inner surface thereof, a removably fixingarrangement, not shown, by which the closure element 6 can removablyengage with the neck 18 of the container. The removably fixingarrangement may comprise, for example, an inner thread intended toengage with an outer thread 17, shown in FIG. 3, formed on the neck 18.

The skirt 11 can be provided, on an outer surface thereof, with aplurality of knurling lines 13, extending parallel to the axis Z andsuitable for facilitating gripping of the cap 1 by the user or by thecapping machine which applies the cap 1 on the container to be closed.

The knurling lines 13 may continue also in the connecting zone 12 and/orin the retaining ring 5.

In the example shown, the skirt 11 comprises a cylindrical portion 14 onwhich the knurling lines 13 are made. The skirt 11 further comprises awide portion 15 having a diameter larger than the cylindrical portion14. The wide portion 15 may be delimited by a smooth outside surface,that is to say, it can be free of knurling lines. This condition is not,however, necessary and the knurling lines could also extend on the wideportion 15. Between the cylindrical portion 14 and the wide portion 15 astep 19 may be provided.

The retaining ring 5 extends between the free edge 16 and the separationline 4. The retaining ring 5 may be delimited by a cylindrical ortruncated cone shaped outer surface. In the closed position of the cap 1shown in FIG. 1, the retaining ring 5 is coaxial with the closureelement 6.

The retaining ring 5 is provided internally with an engagement element20, shown in FIG. 2, suitable for engaging with a circular enlargement23, shown in FIG. 3, which projects from an outer surface of the neck18. The engagement element 20 is configured to abut against the circularenlargement 23 in order to prevent axial movements of the retaining ring5, away from the neck 18, when the closure element 6 is removed from theneck 18.

The engagement element 20 may be shaped like an annular element which isbent around the free edge 16 towards the inside of the retaining ring 5.In an alternative embodiment not illustrated, there may be a pluralityof engagement elements, shaped like tabs which project from the freeedge 16 and are bent towards the inside of the retaining ring 5.Alternatively, the engagement element 20 may be shaped like anenlargement, continuous or interrupted, which from an inner surface ofthe retaining ring 5 projects towards the axis Z to engage with thecircular enlargement 23.

As shown in FIG. 1, the cap 1 has an incision line 21 which extends onthe side wall 2 transversally, in particular perpendicularly, to theaxis Z. In more detail, the incision line 21 is interposed between theseparation line 4 and the free edge 16.

If the cap 1 is positioned in the same orientation which it will haveafter having been applied to the container, that is to say, with thetransversal wall 3 facing upwards, the incision line 21 is arrangedbelow the separation line 4. The incision line 21 is therefore locatedon the side of the retaining ring 5, relative to the separation line 4.

The joining portion 8 is located on the opposite side of the incisionline 21 relative to the retaining ring 5. The incision line 21 thereforedelimits the joining portion 8 towards the retaining ring 5.

The incision line 21 has an angular extension A1, measured about theaxis Z, greater than the angular distance (also measured about the axisZ) between the first end 9 and the second end 10 of the separation line4, that is to say, the angular dimension W of the joining portion 8. Forexample, the angular extension A1 of the incision line 21 may be between60° and 200°, preferably between 75° and 180°. The angular dimension Wof the joining portion 8 about the axis Z, that is to say, the angulardistance between the first end 9 and the second end 10 of the separationline 4, may be between 5° and 40°, preferably between 10° and 30°.

In the example illustrated, the joining portion 8 is centred relative tothe separation line 21. In other words, the midpoint of the separationline 21 and the centre line of the joining portion 8 are aligned witheach other in a direction parallel to the axis Z, that is to say, theylie in a common plane which contains the axis Z. This condition is nothowever necessary, since even a not perfectly centred positioning of theincision line 21 relative to the joining portion 8 is permitted.

In the example illustrated, the incision line 21 has a flat archedshape. However, other shapes are possible.

The incision line 21 and the separation line 4 may be parallel to eachother, even though this condition is not necessary. For example, theincision line 21 and the separation line 4 could be slightly inclinedrelative to each other. Alternatively, the incision line 21 couldcomprise a plurality of stretches having different inclinations, notnecessarily parallel to each other.

As shown in FIG. 1, the incision line 21 has an end 27 and a further end28. The end 27 extends outside the joining portion 8, beyond the firstend 9 of the separation line 4. The further end 28 also extends outsidethe joining portion 8, but goes beyond the second end 10 of theseparation line 4.

The incision line 21 comprises a central part 24 interposed between aperipheral part 25 and a further peripheral part 26. The central part 24faces the joining portion 8. The peripheral part 25 faces the separationline 4, in particular an end portion of the separation line 4. Moreprecisely, the peripheral part 25 faces the separation line 4 in a zonebetween the first end 9 of the separation line 4 and the end 27 of theincision line 21. The further peripheral part 26 faces the separationline 4, in particular a further end portion of the separation line 4.More precisely, the further peripheral part 26 faces the separation line4 in a zone between the second end 10 of the separation line 4 and thefurther end 28 of the incision line 21.

Between the peripheral part 25 of the incision line 21 and a portion ofthe separation line 4 which starts from the first end 9, a connectingband 29 is defined for connecting the joining portion 8 to the retainingring 5. Similarly, between the further peripheral part 26 of theincision line 21 and a further portion of the separation line 4 whichstarts from the second end 10, a further connecting band 30 is definedfor connecting the joining portion 8 to the retaining ring 5.

In the example illustrated, the connecting band 29 and the furtherconnecting band 30 are arranged symmetrically to each other relative toa plane containing the axis Z and a centre line of the joining portion8.

The incision line 21 may be shaped as a through cut which passes throughthe entire thickness of the side wall 2. Even though this feature is notshown in the drawings, along the incision line 21 there may be one ormore breakable elements intended to break the first time the cap 1 isopened.

Alternatively, the incision line 21 may be shaped as a weakening linethat does not pass through the entire thickness of the side wall 2, butat which the thickness of the side wall 2 is reduced with respect to thesurrounding zones.

At the first end 9 and at the second end 10 of the separation line 4,and/or at the end 27 and at the further end 28 of the incision line 21,there may be incision zones 38, shown in FIG. 1. The incision zones 38may have a circular geometry and in general have a transversal dimensiongreater than a width of the corresponding incision line or separationline. This makes it possible to prevent the propagation of fracturecracks starting from the incision or separation lines. In an alternativeembodiment, the incision zones 38 may be absent.

In a central part of the joining portion 8 there may be a stressreduction cut 39, having dimensions very limited relative to thedimensions of the joining portion 8, so as to not adversely affect theresistance of the joining portion 8. The stress reduction cut 39 makesit possible to increase the deformability of the central part of thejoining portion 8, reducing the tensions in the surrounding zones. Thepresence of the weight reduction cut 39 is optional.

The cap 1 is applied on the neck 18 of the container in the closedposition shown in FIG. 1. The cap 1 is positioned in such a way that theengagement element 20 provided inside the retaining ring 5 is below thecircular enlargement 23 present on the neck 18.

When the user wishes to open the container for the first time, the usergrips the skirt 11 of the closure element 6 and rotates the closureelement 6 about the axis Z, in order to unscrew the closure element 6from the neck 18. Initially, the closure element 6 and the retainingring 5 are rotated together about the axis Z, and they simultaneouslymove together in a direction parallel to the axis Z, away from the neck18. This occurs until the engagement element 20 of the retaining ring 5abuts against the circular enlargement 23 provided on the neck 18. Atthis point, the circular enlargement 23 prevents the retaining ring 5from rising further along the axis Z, acting as a stop for the movementof the retaining ring 5 away from the neck 18.

The closure element 6, which is unscrewed by the user, continues to movealong the axis Z away from the neck 18. The breakable bridges 7 arethereby tensioned, until causing their failure. The closure element 6consequently separates from the retaining ring 5 along the separationline 4, but remains joined to the retaining ring 5 at the joiningportion 8.

If the user continues to unscrew the closure element 6, so as to movethe closure element 6 along the axis Z to remove it from the neck 18,the first connecting band 29 and the second connecting band 30 deform.In particular, by moving the closure element 6 upwards, the firstconnecting band 29 and the second connecting band 30 are also pulledupwards. Consequently, the first connecting band 29 and the secondconnecting band 30 are spaced apart from both the closure element 6 andthe retaining ring 5 and remain joined to each other in the joiningportion 8.

The first connecting band 29 and the second connecting band 30 thusadopt a kind of trapezium shape as shown in FIG. 2, in which the neck 18of the container is not shown. In this configuration, the firstconnecting band 29 remains joined to the retaining ring 5 at the end 27of the incision line 21. Similarly, the second connecting band 30remains joined to the retaining ring 5 at the further end 28 of theincision line 21.

The first connecting band 29 and the second connecting band 30 arejoined to each other in the joining portion 8.

In other words, the first connecting band 29 and the second connectingband 30 are arranged in an inclined configuration relative to theretaining ring 5 and converge in the joining portion 8.

Continuing to unscrew the closure element 6, the latter is disengagedfrom the outer thread 17 made on the neck 18, so that the container canbe opened. The retaining ring 5 remains, however, anchored to the neck18. The first connecting band 29, the second connecting band 30 and thejoining portion 8 define a hinge arrangement 40, shown in FIG. 3, aboutwhich the closure element 6 can rotate to allow the user to access thecontents of the container.

In particular, by moving the closure element 6 about the hingearrangement 40 after the closure element 6 has been disengaged from theneck 18, it is possible to move the closure element 6 to a lateralposition relative to the neck 18, so that the closure element 6 is nolonger coaxial with the retaining ring 5, as shown in FIG. 3. Theclosure element 6 may be rotated further backwards relative to theposition shown in FIG. 3, in order to move it further away from the neck18 and to allow the user to more easily access the contents of thecontainer.

After use, the user can return the cap 1 to the closed position shown inFIG. 1 by a sequence of operations in reverse order compared with thatpreviously described.

The first connecting band 29 and the second connecting band 30 allow ahinge arrangement 40 to be obtained which is longer than that whichwould be available if only the hinge band defined by the joining portion8 were present. This makes it easier to disengage the closure element 6from the neck 18, and reapply the closure element 6 on the neck 18, byrotating the closure element 6 about the hinge arrangement 40.

The capacity for rotating the closure element 6 about the hingearrangement 40 may be further increased by using a cap 101 according tothe alternative embodiment shown in FIG. 4.

The cap 101 shown in FIG. 4 has many similarities to the cap 1 shown inFIGS. 1 to 3. In particular, the incision line 21, the separation line4, the joining portion 8, the first connecting band 29 and the secondconnecting band 30 are present and are structurally and functionally thesame as those described with reference to FIGS. 1 to 3.

The cap 101 differs from the cap 1 because the side wall 2 has a pair ofbreak lines 41 which, from the joining portion 8, extend towards thetransversal wall 3.

In particular, a first break line of the above-mentioned pair of breaklines 41 extends from the first end 9 of the separation line 4 towardsthe transversal wall 3, whilst a second break line extends from thesecond end 10 of the separation line 4 towards the transversal wall 3.

Between the break lines 41 a flexible strap 42 which connects theclosure element 6 to the joining portion 8.

In the example illustrated, the break lines 41 are parallel to eachother, even though this condition is not necessary.

In the example illustrated, the break lines 41 extend parallel to theaxis Z. However, this condition too is not necessary and the break lines41 could be slightly inclined relative to the axis Z.

The break lines 41 may have the same length.

The break lines 41 may be shaped as cuts which pass through the entirethickness of the closure element 6. In this case, along the break lines41 there may be one or more joining points intended to be broken thefirst time the cap 101 is moved to the open position.

In an alternative embodiment, the break lines 41 may be shaped asweakening lines at which the closure element 6 has a thickness which isreduced with respect to the surrounding zones. Along those weakeninglines, the material of which the closure element 6 consists is intendedto break, the first time the cap 101 is opened.

In order to move the cap 101 to the open position, the procedure is aspreviously described with reference to FIGS. 1 to 3. In particular, theclosure element 6 of the cap 101 is unscrewed from the neck 18, untilthe position shown in FIG. 4 is reached, wherein the inner thread formedin the closure element 6 is completely disengaged from the outer thread17 formed on the neck 18. At this point, the closure element 6 of thecap 101 may be rotated backwards by an angle greater than for theclosure element 6 of the cap 1, owing to the break lines 41, whichincrease the flexibility and the deformability of the correspondinghinge arrangement.

FIGS. 5 to 7 and 10 show a cap 201 according to another embodiment.

The parts of the cap 201 common to the cap 1 described with reference toFIGS. 1 to 3 will be indicated with the reference numbers already usedin FIGS. 1 to 3 and, for brevity, will not be described again in detail.What was previously described with reference to the cap 1 shall beunderstood to also be applicable to the cap 201, unless differences areexplicitly provided. As shown in FIGS. 5 to 7 and 10, the cap 201comprises the side wall 2 which extends about the axis Z, and thetransversal wall 3 located at an end of the side wall 2, so as to closethat end.

The cap 201 is further provided with the separation line 4, positionedon the side wall 2, which defines on the cap 201 the retaining ring 5and the closure element 6. The retaining ring 5 is intended to remainanchored to the neck of the container on which the cap 201 is applied,owing to at least one engagement element provided inside it. Incontrast, the closure element 6 is suitable for removably engaging withthe neck, owing to the removably fixing arrangement provided inside theskirt 11. In this way, the closure element 6 is movable between a closedposition, shown in FIGS. 5 and 6, and an open position, shown in FIG.10.

The separation line of 4 extends about the axis Z and iscircumferentially interrupted so as to define on the side wall 2 thejoining portion 8 by which the closure element 6 is joined to theretaining ring 5.

The incision line 21 is further provided on the side wall 2. In theexample illustrated, the incision line 21 is axially interposed betweenthe free edge 16 of the retaining ring 5 and the separation line 4.

Two connecting bands, that is to say, a connecting band 29 and a furtherconnecting band 30, are defined between the separation line 4 and theincision line 21, the two connecting bands joining the retaining ring 5to the joining portion 8.

In particular, the connecting band 29 extends between the peripheralpart 25 of the incision line 21 and a portion of the separation line 4which starts from the first end 9 of the later. Similarly, the furtherconnecting band 30 extends between the further peripheral part 26 of theincision line 21 and a further portion of the separation line 4 whichstarts from the second end 10. The connecting band 29 and the furtherconnecting band 30 may be arranged symmetrically to each other relativeto a plane containing the axis Z and a centre line of the joiningportion 8.

FIGS. 8 and 9 show a neck 218 on which the cap 201 may be applied. Theneck 218 extends about a longitudinal axis Z1. When the cap 201 isapplied on the neck 218 and the closure element 6 is in the closedposition, the axis Z of the side wall 2 coincides with the longitudinalaxis Z1.

The neck 218 is delimited by an outer surface 219, which in the exampleillustrated is cylindrical and coaxial with the longitudinal axis Z1.

The outer surface 219 extends as far as a rim 220 of the neck 218. Therim 220 surrounds an opening 221 through which it is possible to accessthe container, when the closure element 6 is in the open position. Viceversa, the closure element 6 closes the opening 221 when it is arrangedin the closed position.

The neck 218 comprises a collar 222, suitable for preventing theretaining ring 5 from descending along the neck 218 below apredetermined level.

Moreover, the collar 222 may be used for conveying the container duringthe production, filling and capping process.

The outer surface 219 extends from the collar 222 to the rim 220.

A circular enlargement 223 projects from the outer surface 219, thecircular enlargement 223 being suitable for engaging with the engagementelement provided inside the retaining ring 5 so as to prevent theretaining ring 5 from being detached from the neck 218.

The circular enlargement 223 may comprise a truncated cone shapedportion 224, whose diameter increases in a direction going from the rim220 towards the collar 222.

The circular enlargement 223 is delimited, on the opposite side to therim 220, by an abutment surface 225 against which the at least oneengagement element of the retaining ring 5 abuts.

A cylindrical portion of the circular enlargement 223 may be interposedbetween the truncated cone shaped portion 224 and the abutment surface225.

However, other geometries of the circular enlargement 223 are possible.

The neck 218 comprises at least one removable fixing element with whichthe removably fixing arrangement formed inside the closure element 6 canengage to allow the closure element 6 to be alternatively applied on, orremoved from, the neck 218.

The at least one removable fixing element may comprise an outer thread217 formed on the outer surface 219, in particular projecting from theouter surface 219.

The cap 201 is intended to be applied on the neck 218 when the closureelement 6 is in the closed position. In particular, the cap 201 isapplied on the neck 218 in such a way that the at least one engagementelement provided inside the retaining ring 5 is below the circularenlargement 223, in particular in a position interposed between thecollar 222 and the circular enlargement 223.

When the user acts on the cap 201 to move the closure element 6 to theopen position for the first time, the closure element 6 is unscrewed,that is to say, it is rotated about the longitudinal axis Z1 andsimultaneously moved away from the collar 222. The retaining ring 5,joined to the closure element 6 by the breakable bridges 7, initiallymoves together with the closure element 6. When the at least oneengagement element provided inside the retaining ring 5 abuts againstthe abutment surface 225, the retaining ring 5 cannot rise any furtheralong the neck 218. On the other hand, the closure element 6 movesfurther away from the body of the container and simultaneously rotatesabout the longitudinal axis Z1, gradually as the user continues tounscrew the closure element 6. In this way, the breakable bridges 7arranged along the separation line 4 are subjected to a stress thatcauses them to break. The connecting bands 29, 30 also deform while theclosure element 6 is unscrewed. In particular, gradually as the closureelement 6, during unscrewing, is moved away from the retaining ring 5,the connecting bands 29, 30 are positioned in an inclined positionrelative to the retaining ring 5, detaching from the retaining ring 5along the incision line 21. The closure element 6 also detaches from theconnecting bands 29, 30. Any breakable elements positioned along theincision line 21 break.

In this way, the position shown in FIG. 7 is reached, wherein the neckhas not been shown. The position shown in FIG. 7 may be defined as adisengaged position, because in the position shown in FIG. 7 theremovably fixing arrangement formed inside the closure element 6 hasdisengaged from the thread 217 of the neck 218.

At this point, the closure element 6 may be rotated relative to theretaining ring 5 for displacing it into the open position shown in FIG.10, in which the closure element 6 is arranged on one side of the neck218 and the axis Z of the closure element 6 no longer coincides with thelongitudinal axis Z1 of the neck 218.

The connecting bands 29, 30 are deformable, in such a way that not justthe closure element 6, but also the joining portion 8 is rotatedrelative to the neck 218.

As is shown more clearly in FIG. 7, the joining portion 8 is delimitedby an edge 50 which, in the closed position of the closure element 6(and in general before the closure element 6 is rotated relative to theretaining ring 5 to be moved to the open position) faces the retainingring 5. More specifically, the edge 50 is defined on the side wall 2,towards the closure element 6, by the incision line 21.

When the closure element 6 passes from the disengaged position to theopen position, the joining portion 8 is overturned relative to the neck218. Consequently, the edge 50, which in the disengaged position (andalso in the closed position) was facing the retaining ring 5, ispositioned in such a way that it is facing towards the rim 220 of theneck 218, that is to say, upwards in FIG. 10.

In order to make that possible, the joining portion 8, and in particularits edge 50, slides along the truncated cone shaped portion 224 of thecircular enlargement 223 and simultaneously rotates relative to theconnecting bands 29, 30. The edge 50 reaches a height which is higherthan the circular enlargement 223, assuming that the neck 218 ispositioned in such a way that the opening 221 is facing upwards. Thejoining portion 8 is thus positioned at least partly above the circularenlargement 223, resting on the neck 218. In particular, the joiningportion 8 rests on the outer surface 219 above the circular enlargement223.

In this way, an interference is generated between the neck 218 and thejoining portion 8, in particular along the edge 50 and near the latter.There may also be interference between the connecting bands 29, 30 andthe neck 218. This allows the closure element 6 to be stably kept in theopen position. In effect, in order to bring the closure element 6 backto the closed position, it is necessary to overcome the interferencebetween the joining portion 8 and the neck 218. Normally, that does notoccur accidentally, instead only occurring if the user deliberatelyapplies sufficient force to the closure element 6, that is to say, ifthe user wishes to move the closure element 6 to the closed position.

Moreover, the interference which occurs between the joining portion 8and the neck 218 makes it difficult for the cap 201 to be able to rotateabout the neck 218, due to the rotation of the retaining ring 5 aboutthe neck 218. In effect, the retaining ring 5 is connected to thejoining portion 8 by the connecting bands 29, 30. Consequently, theretaining ring 5 is not free to rotate about the neck 218, instead itcan only rotate if the interference between the joining portion 8 andthe neck 218 is overcome.

In order to make it possible for the joining portion 8 to rotate whenthe closure element 6 passes from the disengaged position to the openposition, the connecting bands 29, 30 are subjected to twisting, whichaffects at least part of the height H of each connecting band 29, 30.The term “height H” of the connecting bands 29, 30 refers to thedimension of the connecting bands 29, 30 in a direction parallel to theaxis Z of the side wall 2, when the closure element 6 is in the closedposition, as shown in FIG. 5.

In the example illustrated, wherein the separation line 4 and theincision line 21 lie in respective planes parallel to each other, theheight H of the connecting bands 29, 30 is constant along the entirelength of the connecting bands 29, 30 and is equal for the twoconnecting bands 29, 30. As shown in FIGS. 5 to 7 and 10, the knurlinglines 13 are provided on the closure element 6. The knurling lines 13may extend parallel to the axis Z.

In the example illustrated, the separation line 4 intersects theknurling lines 13. In other words, the knurling lines 13 extend on bothsides of, that is to say, both above and below, the separation line 4.

That occurs because the separation line 4 is provided in a position asclose as possible to the removably fixing arrangement arranged insidethe closure element 6, that is to say, to the inner thread. In this way,it is possible to increase the height H of the connecting bands 29, 30.

Consequently, as shown in FIG. 10, the connecting bands 29, 30 comprisea first portion 51 provided with knurling lines 13 and a second portion52 which is smooth. A widened part 53 may be provided between the firstportion 51 and the second portion 52.

In the example illustrated, when the joining portion 8 rotates so thatthe edge 50 is facing towards the rim 220, the second portion 52 of theconnecting bands 29, 30 twists and passes under the first portion 51.The first portion 51, like the widened part 53, if present, in contrastexpands radially, but does not undergo substantial twisting.

Owing to deformation of the connecting bands 29, 30, the joining portion8 can rest on the neck 218 with the edge 50 facing towards the rim 220,without it being necessary to provide weakening lines or fracture linesin the joining portion 8 and/or in the connecting bands 29, 30. In thisway, production of the cap 201 is not complicated.

In the closed position, when the edge 50 faces the retaining ring 5,there is an albeit small amount of play between the joining portion 8and the neck 218. When the closure element 6 is moved to be brought tothe open position, the joining portion 8 begins to rotate and starts tointerfere with the neck 218. The interference between the joiningportion 8 and the neck 218 reaches a maximum value when the joiningportion 8 is approximately arranged in a plane perpendicular, or almostperpendicular, to the neck 218, or rather to its longitudinal axis Z1.The interference between the joining portion 8 and the neck 218 isreduced when the joining portion 8 is overturned, that is to say, whenthe edge 50 moves above the connecting bands 29, 30. In the openposition, the interference between the joining portion 8 and the neck218 remains, although it is less than the maximum value.

When the position in which the interference reaches a maximum value ispassed, the user who is manually rotating the closure element 6 in orderto move it to the open position can feel a sort of vibration. Thatvibration is perceived by the hand of the user, who is moving theclosure element 6, as a discontinuity in the movement of the closureelement 6. In other words, the closure element 6 snaps into place beyondthe position in which the interference between the joining portion 8 andthe neck 218 reaches the maximum value, and the user perceives this snapmotion.

In this way the user is certain that the closure element 6 has beencorrectly moved to the open position.

It is also possible, but not necessary, for the vibration to beaccompanied by a sound such as a “click”, which can be heard by theuser.

The cap 201 described above guarantees not just that the closure element6 stably remains in the open position, but also that, in the openposition, the closure element 6 is rotated backwards, relative to theneck, by a relatively wide angle of opening A1, as shown in FIG. 10.

In particular, the angle A1 may be greater than, or equal to, 140°. Thismakes it very difficult for the closure element 6 to be able in anunwelcome way to strike the face of the user who is drinking directlyfrom the bottle on which the cap 201 is applied, or for the closureelement 6 to be able to obstruct the dispensing of a liquid contained inthe bottle into a container, such as a glass.

Experimentation has shown that several geometric parameters of the cap201 and/or of the neck 218 favour the behaviour previously describedwith reference to FIG. 10.

In particular, on the neck 218 it is possible to define an external ormaximum diameter Dmax of the circular enlargement 223, as shown in FIG.8. It is also possible to define a diameter Ds of the outer surface 219of the neck 218, immediately above the circular enlargement 223, that isto say, in a position interposed between the circular enlargement 223and the outer thread 217. In the example illustrated, the diameter Dsimmediately above the circular enlargement 223 coincides with thediameter of the outer surface 219 in a region interposed between theouter thread 217 and the rim 220, but this condition is not necessary.

Delta indicates the difference between the external diameter Dmax of thecircular enlargement 223 and the diameter Ds of the outer surface 219immediately above the circular enlargement 223.

In the example illustrated, the external diameter Dmax of the circularenlargement 223 is 30.2 mm.

The diameter Ds of the outer surface 219 immediately above the circularenlargement 223 is 28 mm.

The difference Delta between Dmax and Ds is 30.2−28=2.2 mm.

Half of the difference Delta expresses how far the circular enlargement223 projects relative to the outer surface 219.

As already said, H indicates the height of the connecting bands 29, 30,that is to say, the distance between the separation line 4 and theincision line 21, measured parallel to the axis Z, when the closureelement 6 is in the closed position.

In the example illustrated, the height H is 2.8 mm.

The ratio R1 between the height H and half of the difference Delta istherefore 2.8/1.1, that is to say, 2.55.

It is advisable for the ratio R1 between the height H and half of thedifference Delta, as they are defined above, to be greater than, orequal to 1.5. It is preferable for the above-mentioned ratio R1 to begreater than, or equal to, 2. It is even more preferable for R1 to begreater than, or equal to, 2.5.

That ensures that the height H of the connecting bands 29, 30 iscorrectly proportionate to how far the circular enlargement 223 projectsfrom the outer surface 219.

More specifically, if the ratio R1 is less than 1.5, it may happen thatbetween the joining portion 8 and the neck 218 the interference createdis not sufficient to stably lock the closure element 6 in an openposition in which the angle of opening A1 is greater than, or equal to,120°, preferably greater than, or equal to, 140°.

In the example illustrated, half of the difference Delta between theexternal diameter Dmax of the circular enlargement 223 and the diameterDs of the outer surface 219 of the neck 218, immediately above thecircular enlargement 223, is Delta/2=1.1 mm.

It is possible to obtain a cap 201 which works correctly even withvalues of the difference Delta other than those mentioned above. Ingeneral, experimentation has shown that relatively low values of thedifference Delta (and therefore of Delta/2) are helpful for obtaining abehaviour of the type shown in FIG. 10.

The joining portion 8 has an angular dimension W about the axis Z of theside wall, which has been explicitly indicated in FIG. 1 and which isdefinable in the same way with reference to the cap 201.

In the example illustrated, the angular dimension W of the joiningportion 8 is 54°.

In general, the angular dimension W may be greater than, or equal to,20°, preferably greater than, or equal to, 25°.

Moreover, the angular dimension W may be less than, or equal to, 120°,preferably less than, or equal to, 90°.

Experimentation has shown that, if the angular dimension W is greaterthan 120°, the connecting bands 29, 30 may break, when the closureelement 6 is rotated in order to move it to the open position.

In contrast, if W is less than 20°, it may happen that the joiningportion 8 does not succeed in stably keeping the closure element 6 in anopen position in which the opening angle A1 is greater than, or equalto, 120°, preferably greater than, or equal to, 140°.

It is also possible to define a distance Y, shown in FIG. 8, between thecircular enlargement 223 and the at least one removable fixing elementprovided on the neck 219. In other words, the distance Y is measuredbetween the upper limit of the circular enlargement 223 and the startingpoint of the outer thread 217.

The distance Y may be greater than, or equal to, half of the distancebetween the separation line 4 and the incision line 21, that is to say,half the height H. However, this condition is not necessary.

It is possible to define an angle A, indicated in FIG. 8, formed betweena generatrix of the truncated cone shaped portion 224 and a straightline parallel to the longitudinal axis Z1.

In the example illustrated, the angle A is 30°.

More generally, the angle A is preferably less than, or equal to, 35°.

That reduces the risk of the joining portion 8 not sliding correctly onthe circular enlargement 223, in particular near the external diameterDmax, for then stably stopping in contact with the neck 218.

When the user wishes to reclose the container, the closure element 6 canbe returned to the closed position with a sequence of operations inreverse order compared with that previously described. In particular,the user rotates the closure element 6 relative to the neck 218 in orderto return it to the closed position. Consequently, the joining portion 8is also rotated, so as to return the edge 50 below the connecting bands29, 30, in a position facing the retaining ring 5. When the edge 50disengages from the neck 218, the user perceives a vibration orsnap-motion feedback, which may (but not necessarily) be accompanied bya “click” sound. In this way, the user realises that the closure element6 is ready to be screwed onto the neck 218 again. In effect, thedisengagement position has been reached, starting from which the closureelement 6 can be screwed onto the neck 218 again for moving it to theclosed position.

In the example described so far, the separation line 4 is located in aportion of the side wall 2 wherein the knurling lines 13 are present.

However, this condition is not necessary. In an alternative embodimentnot illustrated, the separation line 4 may be made in a portion of theside wall 2 wherein the latter is externally delimited by asubstantially smooth outer surface. That is to say, the separation line4 may be positioned in a portion of the side wall 2 free of knurlinglines 13, for example interposed between the knurling lines 13 and thefree edge 16. Consequently, in the alternative embodiment justdescribed, the connecting bands 29, 30 are externally delimited by asmooth surface, that is to say, a surface free of knurling lines.

The cap 201 is also particularly easy to make.

In effect, the cap 201 may be obtained starting from a concave bodycomprising the side wall 2 and the transversal wall 3. The concave bodyis produced by moulding a polymeric material, for example compressionmoulding or injection moulding.

After the concave body has been formed, the separation line 4 and theincision line 21 are made on the side wall 2.

The separation line 4 and the incision line 21 may be made by cuttingoperations, for example performed in a cutting unit located downstreamof a mould in which the concave body has been formed. Such cuttingoperations may be performed by respective blades, for example circularor linear, which interact with the side wall 2 from the outside of thelatter, or from the inside. In particular, the concave body may berotated about the axis Z of the side wall 2, while the blades are heldin their position, so as to bring consecutive zones of the side wall 2to interact, one after another, with the blades. It is also possible tohold the concave body in its position and to rotate the blades, formaking the cut.

The blades which allow the separation line 4 and the incision line 21 tobe obtained may be configured to interact with the side wall 2 inrespective parallel planes, for example perpendicular to the axis Z, if,as in the desired examples, the separation line 4 and the incision line21 are to lie in respective parallel planes.

The blades may have an interrupted cutting edge, if, along theseparation line 4 the breakable bridges 7 are to remain defined and/orif, along the incision line 21, respective breakable elements are toremain defined.

It is also possible that the blades do not cut through the entirethickness of the side wall 2, instead only partially cutting throughthickness of the side wall 2, so as to leave, along the incision line 21and/or along the separation line 4, a thin membrane intended to bebroken the first time the cap is opened.

The separation line 4 and the incision line 21 may be madesimultaneously, or during two separate steps.

The cap 201 is therefore particularly easy to produce, since the concavebody can be formed in an ordinary mould. There is no need for undercutparts or thin parts other than those normally provided for a cap of theknown type.

An additional operation, that is to say, making the incision line 21,may be performed very simply while the separation line 4 is obtained.

FIGS. 11 and 12 show a cap 301 for closing a container, particularly abottle intended to contain a liquid substance such as a drink. The cap301 is made of polymeric material. Any polymeric suitable for beingmoulded can be used to obtain the cap 301.

The cap 301 is shown in FIGS. 11 and 12 in a closed position in whichthe cap 301 is when it leaves a cap production line, ready to be appliedon the container. In this condition, the cap 301 comprises a side wall302 which extends about an axis Y, and a transversal wall 303 located atan end of the side wall 302, so as to close the end. The transversalwall 303 extends transversally, in particular perpendicularly, to theaxis Y. The transversal wall 303 may be flat, even though other shapesare theoretically possible. In the example illustrated, the transversalwall 303 has a substantially circular shape in plan view.

The cap 301 has a separation line 304, arranged on the side wall 302 andextending about the axis Y. The separation line 304 extends on a planearranged transversally, in particular perpendicularly, to the axis Y.The separation line 304 forms on the cap 301 a retaining ring 305 and aclosure element 306. The latter are arranged on opposite sides of theseparation line 304. As described in more detail below, when the cap 301is moved to an open position, the closure element 306 separates from theretaining ring 305 along the separation line 304.

Along the separation line 304 there may be a plurality of breakablebridges 307 which connect the retaining ring 305 to the closure element306. The breakable bridges 307 are intended to be broken the first timethe cap 301 is moved to the open position, to signal that the containeris no longer intact. The separation line 304 may be parallel to a freeedge 316 of the cap 301. More specifically, the free edge 316 delimitsthe retaining ring 305 on the opposite side to the transversal wall 303.

The separation line 304 does not extend for an entire angle of 360°about the axis Y. The separation line 304 is interrupted in thecircumferential direction, so as to define on the side wall 302 ajoining portion 308, at which the closure element 306 remains joined tothe retaining ring 305.

In other words, the separation line 304 has a first end 309 and a secondend 310. The joining portion 308 is interposed between the first end 309and the second end 310. At the joining portion 308, the retaining ring305 is joined to the closure element 306.

As shown in FIG. 11, the joining portion 308 has an angular dimension W1about the axis Y.

In the example shown, the closure element 306 has a cup-shaped body andcomprises a skirt 311 which extends about the axis Y. The skirt 311 isconnected to the transversal wall 303, arranged at the end of the skirt311 opposite the separation line 304. More specifically, the skirt 311is connected to the transversal wall 303 by a connecting zone 312, whichmay be shaped, in cross section, like a beveled edge or a circularconnection portion.

The skirt 311 has, on an inner surface thereof, a removably fixingarrangement, not shown, by which the closure element 306 can removablyengage with a neck 318 of the container, shown in FIGS. 14 and 15. Theremovably fixing arrangement can comprise, for example, an inner threadintended to engage with an outer thread 317, shown in FIGS. 14 and 15,formed on the neck 318.

The skirt 311 can have, on an outer surface thereof, a plurality ofknurling lines 313, extending parallel to the axis Y and intended tofacilitate gripping of the cap 301 by the user or by the capping machinewhich applies the cap 301 on the container to be closed.

The knurling lines 313 may continue also in the connecting zone 312and/or in the retaining ring 305.

In the example shown, the skirt 311 comprises a cylindrical portion 314on which the knurling lines 313 are made. The skirt 311 also comprises awide portion 315 having a diameter larger than the cylindrical portion314. The wide portion 315 may be delimited by a smooth outside surface,that is to say it can be free of knurling lines. This condition is not,however, necessary and the knurling lines could also extend on the wideportion 315. Between the cylindrical portion 314 and the wide portion315 there may be a step 319.

The retaining ring 305 extends between the free edge 316 and theseparation line 304. The retaining ring 305 may be delimited by acylindrical or truncated cone shape outer surface. In the closedposition of the cap 301 shown in FIG. 11, the retaining ring 305 iscoaxial with the closure element 306.

The retaining ring 305 is provided internally with an engagement element320, shown in FIG. 13, suitable for engaging with a circular enlargement323, shown in FIG. 14, which projects from an outer surface of the neck318. The engagement element 320 is configured to abut against thecircular enlargement 323 so as to prevent axial movements of theretaining ring 305, away from the neck 318, when the closure element 306is removed from the neck 318.

The engagement element 320 may be shaped like an annular element whichis bent around the free edge 316 towards the inside of the retainingring 305. In an alternative embodiment not illustrated, there may be aplurality of engagement elements, shaped like tabs which project fromthe free edge 316 and are bent towards the inside of the retaining ring305. Alternatively, the engagement element 320 may be shaped like anenlargement, continuous or interrupted, which from an inner surface ofthe retaining ring 305 projects towards the axis Y to engage with thecircular enlargement 323.

As shown in FIGS. 11 and 12, the cap 301 has a first incision line 321and a second incision line 322 provided on the side wall 302 and lyingon two levels different to each other. More specifically, if the cap 301is positioned in the same orientation which it will have after havingbeen applied to the container, that is to say, with the transversal wall303 facing upwards, the first incision line 321 is arranged below theseparation line 304. On the other hand, the second cut 322 is arrangedabove the separation line 304. In other words, the first incision line321 and the second incision line 322 are arranged on opposite sides ofthe separation line 304.

The first incision line 321 is arranged in a position closer to the freeedge 316 than the second incision line 322. In effect, the firstincision line 321 is arranged on the side of retaining ring 305,relative to the separation line 304.

The second incision line 322 is arranged in a position closer to thetransversal wall 303 than the first incision line 321. In effect, thesecond incision line 322 is arranged on the side of the closure element306, relative to the separation line 304.

The joining portion 308 is interposed between the first incision line321 and the second incision line 322. The first incision line 321 andthe second incision line 232 extend transversely to the axis Y,delimiting the joining portion 308 on opposite sides of the separationline 304.

In other words, the first incision line 321 and the second incision line322 face each other, that is to say, are not offset, so that the joiningportion 308 is interposed between them.

The first incision line 321 and the second incision line 322 haverespective angular extensions A1 and A2, measured about the axis Y,greater than the angular distance (also measured about the axis Y)between the first end 309 and the second end 310 of the separation line304, that is to say, of the angular dimension W1 of the joining portion308. For example, the angular extension A1 of the first incision line321 and the angular extension A2 of the second incision line 322 may bebetween 60° and 200°, for example between 75° and 180°. The angulardimension W1 of the joining portion 308 about the axis Y, that is tosay, the angular distance between the first end 309 and the second end310 of the separation line 304, may be between 5° and 75°, for examplebetween 10° and 40°.

The first incision line 321 and the second incision line 322 may havethe same angular extension about the axis Y, or angular extensions aboutthe axis Y which are different from each other. In other words, theangular extensions A1 and A2 can be identical or different from eachother.

In the example shown, the joining portion 308 is centred relative to thefirst separation line 321 and to the second separation line 322. Inother words, the midpoint of the separation line 321, the midpoint ofthe separation line 322 and the centre line of the joining portion 308are aligned with each other in a direction parallel to the axis Y, thatis to say, they lie in a common plane which contains the axis Y. Thiscondition is not however necessary, since a slight misalignment betweenthe first incision line 321 and the second incision line 322 ispermitted and/or a not perfectly centred positioning of the firstincision line 321 and the second incision line 322 relative to thejoining portion 308.

In the example shown, the first incision line 321 and the secondincision line 322 each have a flat arched shape. However, other shapesare possible.

The first incision line 321 and the second incision line 322 may beparallel to each other, even though this condition is not necessary. Forexample, the first incision line 321 and the second incision line 322might be slightly inclined relative to each other, or each mightcomprise a plurality of stretches having different inclinations, notnecessarily parallel to each other. In the example shown, the firstincision line 321 and the second incision line extend perpendicularly tothe axis Y, that is to say, they extend on respective planes positionedtransversally, in particular perpendicularly, to the axis Y. However,this condition is also unnecessary.

As shown in FIG. 1, the first incision line 321 has an end 327 and afurther end 328. The end 327 extends outside the joining portion 308,beyond the first end 309 of the separation line 304. The further end 328also extends outside the joining portion 308, but goes beyond the secondend 310 of the separation line 304.

The first incision line 321 comprises a central part 324 interposedbetween a peripheral part 325 and a further peripheral part 326. Thecentral part 324 faces the joining portion 308. The peripheral part 325faces the separation line 304, in particular an end portion of theseparation line 304. More precisely, the peripheral part 325 faces theseparation line 304 in a zone between the first end 309 of theseparation line 304 and the end 327 of the first incision line 321. Thefurther peripheral part 326 faces the separation line 304, in particulara further end portion of the separation line 304. More specifically, thefurther peripheral part 326 faces the separation line 304 in a zonebetween the second end 310 of the separation line 304 and the furtherend 328 of the first incision line 321.

Between the peripheral part 325 of the first incision line 321 and aportion of the separation line 304 which starts from the first end 309,a connecting band 329 is defined for connecting the joining portion 308to the retaining ring 305. Similarly, between the further peripheralpart 326 of the first incision line 321 and a further portion of theseparation line 304 which starts from the second end 310, a furtherconnecting band 330 is defined for connecting the joining portion 308 tothe retaining ring 305.

The second incision line 322 has an end 331 and a further end 332. Theend 331 extends outside the joining portion 308, beyond the first end309 of the separation line 304. The further end 332 also extends outsidethe joining portion 308, but goes beyond the second end 310 of theseparation line 304. The second incision line 322 comprises a centralportion 333 interposed between a peripheral portion 334 and a furtherperipheral portion 335. The central portion 333 faces the joiningportion 308. The peripheral portion 334 faces the separation line 304,in a zone between the first end 309 of the separation line 304 and theend 331 of the second incision line 322. The further peripheral portion335 faces the separation line 304, in a zone between the second end 310of the separation line 304 and the further end 332 of the secondincision line 322.

Between the peripheral portion 334 of the second incision line 322 and aportion of the separation line 304 which starts from the first end 309,a connecting strip 336 is defined for connecting the joining portion 308to the closure element 306. Similarly, between the further peripheralportion 335 of the second incision line 322 and a further portion of theseparation line 304 which starts from the second end 310, a furtherconnecting strip 337 is defined for connecting the joining portion 308to the closure element 306.

In the example shown, the connecting band 329 and the connecting strip336 are arranged symmetrically to the further connecting band 330 andrespectively to the further connecting strip 337 relative to a planecontaining the axis Y and a centre line of the joining portion 308.

The first incision line 321 is not connected in any way to the secondincision line 322, that is to say, it is isolated from the secondincision line 322. More specifically, on the cap 301 there are noincision lines which pass through the joining portion 308 for joiningthe first incision line 321 to the second incision line 322. Thisprevents adversely affecting the resistance of the joining portion 308.

The first incision line 321 and the second incision line 322 may beshaped as through cuts which pass through the entire thickness of theside wall 302. Even though this feature is not shown in the drawings,along the first incision line 321 and along the second incision line 322there may be one or more breakable elements intended to break the firsttime the cap 301 is opened. Alternatively, the first incision line 321and the second incision line 322 may be shaped as weakening lines thatdo not pass through the entire thickness of the side wall 302, but atwhich the thickness of the side wall 302 is reduced with respect to thesurrounding zones.

At the first end 309 and at the second end 310 of the separation line304, and/or at the end 327 and at the further end 328 of the firstincision line 321, and/or at the end 331 and at the further end 332 ofthe second incision line 322, there can be incision zones 338, shown inFIG. 12. The incision zones 338 may have a circular geometry and ingeneral have a transversal dimension greater than a width of thecorresponding incision line or separation line. This makes it possibleto prevent the propagation of fracture cracks starting from the incisionor separation lines. In an alternative embodiment, the incision zones338 may be absent.

In a central portion of the joining portion 308 there may be a stressreduction incision 339, having dimensions very limited relative to thedimensions of the joining portion 308, so as to not adversely affect theresistance of the joining portion 308. The stress reduction incision 339makes it possible to increase the deformability of the central part ofthe joining portion 308, reducing the tensions in the surrounding zones.The presence of the stress reduction incision 339 is optional.

The cap 301 is applied to the neck 318 of the container in the closedposition shown in FIGS. 11 and 12. The cap 301 is positioned in such away that the engagement element 320 provided in the retaining ring 305is below the circular enlargement 323 present on the neck 318.

When the user wishes to open the container for the first time, the usergrips the skirt 311 of the closure element 306 and rotates the closureelement 306 about the axis Y, in order to unscrew the closure element306 from the neck 318. Initially, the closure element 306 and theretaining ring 305 are rotated together about the axis Y, and theysimultaneously move together in a direction parallel to the axis Y, awayfrom the neck 318. This occurs until the engagement element 320 of theretaining ring 305 abuts against the circular enlargement 323 providedon the neck 318. At this point, the circular enlargement 323 preventsthe retaining ring 305 from rising further along the axis Y, acting as astop for the movement of the retaining ring 305 away from the neck 318.

The closure element 306, which is unscrewed by the user, continues tomove along the axis Y away from the neck 318. The breakable bridges 307are thereby tensioned, until causing the failure. The closure element306 consequently separates from the retaining ring 305 along theseparation line 304, but remains joined to the retaining ring 305 at thejoining portion 308. If the user continues to unscrew the closureelement 306, so as to move the closure element 306 along the axis Y toremove it from the neck 318, the connecting bands 329, 330 and theconnecting strips 336, 337 deform. More specifically, by moving theclosure element 306 upwards, the connecting strips 336, 337 are alsopulled upwards. Consequently, the connecting strips 336, 337 are spacedfrom the closure element 306 and remain joined to each other in thejoining portion 308. The connecting bands 329, 330 are also pulledupwards and consequently move away from the retaining ring 305. Theconnecting bands 329, 330 remain joined to each other in the joiningportion 308.

The connecting bands 329, 330 and the connecting strips 336, 337 thusadopt a “X” shape as shown in FIG. 13, in which the neck 318 of thecontainer is not shown. In this configuration, the first connecting band329 remains joined to the retaining ring 305 at the end 327 of the firstincision line 321. Similarly, the second connecting band 330 remainsjoined to the retaining ring 305 at the further end 328 of the firstincision line 321. The connecting strip 336 remains joined to theclosure element 306 at the end 331 of the second incision line 322. Thefurther connecting strip 337 remains joined to the closure element 306at the further end 332 of the second incision line 322.

The connecting bands 329, 330 and the connecting strips 336, 337 arejoined together in the joining portion 308.

The connecting bands 329, 330 are arranged in an inclined configurationrelative to the retaining ring 305 and converge in the joining portion308.

Similarly, the connecting strips 336, 337 are arranged in aconfiguration which is inclined relative to the closure element 306 andconverge in the joining portion 308, on the opposite side relative tothe connecting bands 329, 330.

Continuing to unscrew the closure element 306, the latter is disengagedfrom the outer thread 317 made on the neck 318, so that the containercan be opened. The retaining ring 305 remains, however, anchored to theneck 318. The connecting bands 329, 330, the connecting strips 336, 337and the joining portion 308 form a hinge arrangement 340, shown in FIG.14, around which the closure element 306 can rotate to allow the user toaccess the contents of the container.

More specifically, by moving the closure element 306 about the hingestructure 340 after the closure element 306 has been disengaged from theneck 318, it is possible to move the closure element 306 to a lateralposition relative to the neck 318, so that the closure element 306 is nolonger coaxial with the retaining ring 305. Moreover, it is possible tovary the orientation of the concavity defined inside the closure element306. The concavity does not therefore remain always facing downwards asoccurs when the closure element 306 is applied to the container in theclosed position.

The “X” configuration as shown in FIG. 13 is reached when the user isterminating the unscrewing of the closure element 306 from the neck 318and the closure element 306 is about to be disengaged from the neck 318.Subsequently, when the closure element 306 is arranged in a lateralposition relative to the neck 318, the connecting bands 329, 330 maymove close again to the retaining ring 305, as shown in FIG. 14. It isnow possible, as shown in FIG. 14, to rotate the closure element aboutan ideal line passing through the end 331 and the further end 332 of thesecond incision line 322, so that the concavity defined inside theclosure element 306 faces mainly downwards.

At this point, as shown in FIG. 15, an edge zone 341 of the closureelement 306, close to the separation line 311, can move towards the neck318 until engaging with a projection that projects from the neck 318towards the outside, for example with a portion of the external thread317. The edge zone 341 may be diametrically opposite the joining portion308.

In this way, the closure element 306 remains stably locked in a lateralposition relative to the neck 318, far from a dispensing opening 342formed inside the neck 318, by which it is possible to access thecontents of the container. This prevents the closure element 306 fromobstructing the access to the container and/or the escape from thecontainer of the substance contained therein, returning to a position inwhich the dispensing opening 342 is at least partly obstructed. Morespecifically, if the container is a bottle containing a liquid which theuser drinks resting his/her lips directly on the neck 318, it possibleto avoid that the closure element 306 recloses prematurely, striking theuser's face.

To summarize, in a first embodiment there is provided a cap for acontainer, comprising a side wall (302) extending about an axis (Y) anda transversal wall (303) arranged at an end of the side wall (302), aseparation line (304) being provided on the side wall (302) fordefining:

-   -   a retaining ring (305) intended to remain anchored to a neck        (318) of the container, and    -   a closure element (306) which can removably engage the neck        (318), so as to open or close the container;

wherein the separation line (304) extends about the axis (Y) and iscircumferentially interrupted to define a joining portion (308) havingan angular dimension (W1) about the axis (Y),

the cap (301) further having a first incision line (321) and a secondincision line (322), which extend transversely to the axis (Y) fordelimiting the joining portion (8) on opposite sides, the first incisionline (321) and the second incision line (322) having respective angularextensions (A1, A2) about the axis (Y) greater than the angulardimension (W1) of the joining portion (308). In a second embodiment,there is provided a cap according to the first embodiment, wherein thefirst incision line (321) delimits at least partially a connecting band(329) and a further connecting band (330) which connect the retainingring (305) to the joining portion (308), and wherein the second incisionline 3(22) delimits at least partially a connecting strip (336) and afurther connecting strip (337) which connect the closure element (306)to the joining portion (308).

In a third embodiment, there is provided a cap according to the secondembodiment, wherein the connecting band (329) is defined between aperipheral part (325) of the first incision line (321) and an endportion of the separation line (304), the further connecting band (330)being defined between a further peripheral part (326) of the firstincision line (321) and a further end portion of the separation line(304).

In a fourth embodiment, there is provided a cap according to the thirdembodiment, wherein the connecting strip (336) is defined between aperipheral portion (334) of the second incision line (322) and the endportion of the separation line (304), the further connecting strip (337)being defined between a further peripheral portion (335) of the secondincision line (322) and the further end portion of the separation line(304).

In a fifth embodiment, there is provided a cap according to any one ofembodiments from the second to the fourth, wherein the connecting band(329) and the connecting strip (336) are positioned symmetrically to thefurther connecting band (330) and respectively to the further connectingstrip (337) relative to a plane containing the axis (Y) and a centreline of the joining portion (308).

In a sixth embodiment, there is provided a cap according to any one ofembodiments from the first to the fifth, wherein, in an open position,the closure element (306) is rotatable about an ideal line passingthrough an end (331) of the second incision line (322) and through afurther end (332) of the second incision line (322), so that an edgezone (341) of the closure element (306) diametrically opposite thejoining portion (308) can be moved towards the joining portion (308) forengaging with the neck (318).

In a seventh embodiment, there is provided a cap according to any one ofembodiments from the first to the sixth, wherein the first incision line(321) is isolated from the second incision line (322).

In an eighth embodiment, there is provided a cap according to any one ofembodiments from the first to the seventh, wherein the first incisionline (321) and the second incision line (322) extend on two levelsdifferent from each other.

In a ninth embodiment, there is provided a cap according to any one ofembodiments from the first to the eighth, wherein the second incisionline (322) is parallel to the first incision line (321).

In a tenth embodiment, there is provided a cap according to any one ofembodiments from the first to the ninth, wherein the first incision line(321) and the second incision line (322) extend on respective planesparallel to a further plane on which the separation line (304) extends,the further plane being interposed between said respective planes.

In an eleventh embodiment, there is provided a cap according to any oneof embodiments from the first to the tenth, wherein the angularextensions (A1, A2) of the first incision line (321) and the secondincision line (322) are equal to each other.

In a twelfth embodiment, there is provided a cap according to any one ofembodiments from the first to the eleventh, wherein the angularextensions (A1, A2) of the first incision line (321) and the secondincision line (322) are each between 60° and 200°, for example between75° and 180°.

In a thirteenth embodiment, there is provided a cap according to any oneof embodiments from the first to the twelfth, wherein the angulardimension (W1) of the joining portion (308) is between 5° and 75°, forexample between 10° and 40°.

In a fourteenth embodiment, there is provided a cap according to any oneof embodiments from the first to the thirteenth, wherein the closureelement (306) is provided with an internal thread intended to engagewith an external thread (317) of the neck (318).

1-30. (canceled)
 31. Combination of a cap for a container and of a neckof a container, wherein the neck is delimited by an outer surface fromwhich a circular enlargement projects, the outer surface extending up toa rim of the neck, and wherein the cap comprises a side wall extendingabout an axis, a separation line being provided on the side wall fordefining: a retaining ring intended to engage with the circularenlargement for remaining anchored to the neck, and a closure elementwhich can removably engage the neck so as to be movable between a closedposition and an open position, wherein the separation line extends aboutthe axis and is circumferentially interrupted for leaving a joiningportion between the retaining ring and the closure element, the capfurther having an incision line which extends transversally to the axisbetween the separation line and a free edge of the retaining ring, sothat two connecting bands are defined between the separation line andthe incision line, the connecting bands joining the retaining ring tothe joining portion, the connecting bands being deformable to allow thejoining portion to rotate when the closure element is brought from theclosed position to the open position, so that an edge of the joiningportion which, in the closed position, faces the retaining ring, isfacing towards the rim of the neck in the open position.
 32. Combinationaccording to claim 31, wherein the connecting bands are deformable by atwisting movement which affects at least a part of the height of eachconnecting band when the closure element is brought from the closedposition to the open position.
 33. Combination according to claim 31,wherein a distance between the separation line and the incision line isequal to, or greater than, 1.5 times half the difference between anexternal diameter of the circular enlargement and a diameter of theouter surface of the neck immediately above the circular enlargement.34. Combination according to claim 31, wherein the joining portion hasan angular dimension about said axis, which is greater than, or equalto, 20° and less than, or equal to, 120°.
 35. Combination according toclaim 31, wherein the joining portion has an angular dimension aboutsaid axis, which is greater than, or equal to, 25° and which is lessthan, or equal to, 90°.
 36. Combination according to claim 31, whereinthe neck is provided with at least one fixing element suitable forengaging with the closure element to allow the closure element to beremovably fixed to the neck, a distance between the circular enlargementand the at least one fixing element being greater than, or equal to,half of a distance between the separation line and the incision line.37. Combination according to claim 31, wherein the circular enlargementis delimited, towards the rim of the neck, by a truncated cone shapedsurface, a generatrix of the truncated cone shaped surface forming anangle which is less than, or equal to, 35° with a straight line parallelto a longitudinal axis of the neck.
 38. Combination according to claim31, wherein the side wall is externally provided with a plurality ofknurling lines, the separation line intersecting the knurling lines. 39.Cap for a container, comprising a side wall extending about an axis anda transversal wall arranged at an end of the side wall, a separationline being provided on the side wall for defining: a retaining ringintended to remain anchored to a neck of the container, and a closureelement which can removably engage the neck so as to open or close thecontainer; wherein the separation line extends about the axis and iscircumferentially interrupted for leaving a joining portion between theretaining ring and the closure element, the cap further having anincision line which extends transversally to the axis between theseparation line and a free edge of the retaining ring, so that twoconnecting bands are defined between the separation line and theincision line, the connecting bands joining the retaining ring to thejoining portion, the joining portion having an angular dimension aboutsaid axis, which is greater than, or equal to, 20° and less than, orequal to, 120°.
 40. Cap according to claim 39, wherein said angulardimension is greater than, or equal to, 25°, and less than, or equal to,90°.
 41. Cap according to claim 39, wherein the incision line lies in aplane arranged perpendicularly to said axis, when the closure element isin a closed position.
 42. Cap according to claim 39, wherein the sidewall is externally provided with a plurality of knurling lines, theseparation line intersecting the knurling lines.
 43. Cap according toclaim 39, wherein the incision line and the separation line are cutlines extending on respective parallel planes.
 44. Cap according toclaim 39, wherein the incision line has an angular extension about theaxis of between 60° and 200°.
 45. Cap according to claim 39, wherein twofracture lines are provided on the side wall, the fracture linesextending towards the transversal wall, respectively from a first endand from a second end of the separation line.
 46. Cap according to claim45, wherein the fracture lines are parallel to each other and to theaxis, the fracture lines having equal length.
 47. Cap according to claim39, wherein the closure element is provided with an inner threadsuitable for engaging with an outer thread of the neck.
 48. Capaccording to claim 39, wherein the separation line has a first end and asecond end, the joining portion, which joins the retaining ring to theclosure element, extending from the first end to the second end.
 49. Capaccording to claim 39, wherein the separation line and/or the incisionline have respective ends at which incision zones having a circulargeometry are provided, for preventing propagation of fracture cracksstarting from the separation line and/or from the incision line.
 50. Capaccording to claim 39, wherein the joining portion has a thicknesssubstantially constant on a plane containing the separation line.